197891321 has 8 divisors (see below), whose sum is σ = 204981504. Its totient is φ = 190845360.

The previous prime is 197891303. The next prime is 197891417. The reversal of 197891321 is 123198791.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-197891321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (197801321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1811 + ... + 19976.

It is an arithmetic number, because the mean of its divisors is an integer number (25622688).

Almost surely, 2^197891321 is an apocalyptic number.

It is an amenable number.

197891321 is a deficient number, since it is larger than the sum of its proper divisors (7090183).

197891321 is a wasteful number, since it uses less digits than its factorization.

197891321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22111.

The product of its digits is 27216, while the sum is 41.

The square root of 197891321 is about 14067.3850093043. The cubic root of 197891321 is about 582.7410102533.

The spelling of 197891321 in words is "one hundred ninety-seven million, eight hundred ninety-one thousand, three hundred twenty-one".